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This overview examines deglacial climate change, highlighting significant findings from radiocarbon dating of the North American ice sheet's retreat. Coral data reveal sea level rise rates, while proxy records document the Younger Dryas, a cold period interrupting deglaciation. Greenland ice cores indicate rapid climatic shifts, and the study explores historical meltwater flows and the influence of tropical monsoons on the northern hemisphere. Additionally, it considers how decreased summer insolation has impacted monsoon strength and regional temperatures over the last 6,000 years.
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Radiocarbon dates showing the retreat of the N. American ice sheet
Proxy records provide evidence for a cold episode (Younger Dryas) that interrupted the deglacial process.
The Greenland ice cores show rapid (<100 yrs) changes in ice accumulation and dust.
Tropical monsoons were stronger in the northern hemisphere 9,000 yrs ago
Proxy records also show tropical monsoon maximum 9,000 yrs ago.
Decreased summer insolation in the northern tropics has produced weaker tropical monsoons.
Decreased summer insolation at high northern latitudes during the last 6,000 yrs coincides with cooler temperatures.
The Little Ice Age could have resulted from orbital-scale cooling or from a millennial-scale oscillation.